It is important to inhibit the formation of a thrombus in preventing and/or treating cardiac infarction, cerebral thrombosis and the like, and various anti-thombotic agents such as anti-thrombin agents and platelet aggregation inhibitors have been developed. Nevertheless, platelet aggregation inhibitors as well as anti-thrombin agents have hemorrhagic side effects and problems in their safety, since these agents possess a platelet aggregation-inhibiting activity in combination with anti-coagulative effect. On the other hand, FXa inhibitors specifically inhibit a coagulation factor, and thus are considered to be useful as anticoagulant.
So far, compounds having FXa-inhibiting effects are disclosed for example in JP 7-112970 A, JP 5-208946 A, WO-96/16940, WO96/40679, WO 96/10022, WO 98/28269, WO 99/37304, WO 99/127, and the like.
Currently, there is a demand for a compound which has a stronger FXa inhibiting activity than that of the above-mentioned compounds having FXa inhibiting activity by oral administration, and is practically excellent as a medicament.